The field of the invention is gun locks and the invention relates more particularly to gun locks for handguns of the type which are inserted in through the muzzle of the gun, extend into the chamber and expand. When expanded, the lock cannot be pulled out of the chamber. Gun locks have been available for many years to help reduce the unauthorized use of a handgun.
A gun lock of the general type as the present gun lock is shown in U.S. Pat. No. 2,479,107. A shaft is inserted into the muzzle of a revolver and when the key is turned, a locking pin is projected and contacts a shoulder in the chamber so that the lock cannot be removed while the locking pin is projected.
U.S. Pat. No. 4,512,099 shows a similar style of lock where the expandable portion has a diagonally split sleeve.
U.S. Pat. No. 5,138,785 has a split shaft with a center cam which expands the shaft outwardly, thereby holding it in the chamber.
U.S. Pat. No. 5,289,653 also utilizes a cam expanded outer sleeve together with a spring loaded adapter which permits the device to be used on guns of different barrel lengths.
U.S. Pat. No. 5,664,358 shows another style of expandable outer sleeve.
A problem with most prior art gun locks is that the gun lock is useful only for a particular gun. A gun dealer would have to stock a large and expensive inventory of gun locks to be prepared to provide a gun lock for the typical wide selection of hand guns available. Not only do barrel lengths differ, but also the bore size differs as does the chamber size.